The oxygen reduction reaction (ORR) is essential in various electrochemical energy conversion processes. However, due to the slow kinetics of the ORR, the use of catalysts comprised of noble elements, such as platinum or platinum alloys, is often desirable. These noble element catalysts are expensive, diminishing the economic viability of electrochemical cells. Replacing noble element catalysts with a less expensive alternative is desirable. Although their high catalytic activity has been hardly challenged, the high price of the precious metal has limited their wide applications.